Summing up my experience.

I’ve wanted an open source 3D printer ever since I first read about a RepRap Mendel in 2009. “Self replicating machines” and “make your own objects”, the article said. It instantly caught my interest with an intensity that way long ago forgotten.

Regardless, I didn’t feel up to the task of building one. Even though the processes of purchase and assembly of parts seemed to be fairly well documented, along with an apparently robust community support, I felt that I wasn’t up to the task as an undergrad architect with hardly any knowledge of electronics or digital fabrication. Was what I remembered from my high school physics enough to deal with the project without frying expensive components? Which extruder should I pick? Should I get a heated bed? What are endstops which ones should I choose? How do I get most of this parts in Brazil without raising the cost to forbidding heights and where do I find substitutes for the (many) ones unavailable? As you can see, the amount of research I’d have to do in order to be able to even know the basics of each of those components to adapt them to my need was overwhelming and I gave up.

Graduation project: the confidence boost.

Then in mid 2012 it was time to graduate and, since the university had a nicely growing FAB LAB, I decided it’d be a great opportunity to work with digital fabrication and boost my knowledge enough so maybe I could build my own extrusion printer. I learned how to use their laser cutters and fabricated my own things for the first time. It was very exciting! Below are two of the best things I’ve made using 3mm MDF:

Even though the laboratory did not own any plastic extrusion machines at the time, another student had partially built one as his graduation project on the previous semester and, at first, I decided to start my project from where he left: I wanted my project to involve prototyping models for architecture with 3d printing. Talking to Arthur Lara (my supervising professor), though, we decided that researching a subject of a more experimental nature would be best practice.

The result of the one-year process is the almost full development of a robotic poly articulated device that, if finished, should be capable of milling soft materials – such as polyurethane foam blocks. It’s controlled through a software built using grasshopper‘s (a plug-in for Rhinoceros) visual programming environment. We intended for it to take a user’s gestures as input, captured by a Microsoft Kinect, (See the hardware schematic view) but unfortunately this part of the design never got implemented because there wasn’t sufficient time to do so.

If you are interested in knowing more specifics of the project, you can read all about it here (automatically translated, as it was originally in Portuguese). Bellow I’ve selected some of the most illustrative images and a video of the working robot:

Testing the set-up:

Hardware details:

Routing DC motor.

Routing DC motor.

Arduinos, DC shield and power adapters.

Cooler mounted on the base.

Assembly detail: internal gear.

Almost fully assembled!

User interface, system assembly schematics and software:

User interface: interaction between user gestures and the Grasshopper/Kinect interface: 1: left hand controls the finer motion of the tip of the routing brush. 2: right hand positions the base of the DC motor in the workspace.

Hardware schematic view, with parts and the sequence of information transmission described.

Software: he general layout of the software. The sliders on the top left indicate where the user gesture data input was going to be received by a specialized component able to communicate with Kinects.

Software component: the blown up view for the custom component labelled 5AxisRobotStructure in the image showing the general layout. This component is responsible for the robot’s joints positioning calculations.